Theory of semi-flexible polymers

We have mapped the physics of a system of semi-flexible inextensible polymers onto a complex Ginzburg-Landau field theory using techniques of functional integration. It is shown in the limit of low number density of monomers in a melt of semi-flexible, inextensible polymers, kept apart by an excluded volume interaction, the radius of gyration scales as N^{nu}, where N is the chain length, and nu = 1, in contrast to the value of nu ~ 0.6 for flexible polymer melts. Using Renormalization Group arguments, we show that the system exhibits an infra-red stable fixed point which can be identified as the transition to the entangled state. Experiments to test these calculations are suggested.